1. Field of the Invention
The present general inventive concept relates to a method and apparatus to build a 3-dimensional grid map, and more particularly, to a method and apparatus to build a 3-dimensional grid map by discerning a peripheral environment using a stereo omni-directional camera, and method and apparatus to control an automatic traveling apparatus.
2. Description of the Related Art
An omni-directional camera is a camera system which takes a picture in all directions at once using a rotating reflector, a condenser lens, and an image pickup device and is applied to security facilities, surveillance cameras, robot visions, etc. The rotating reflector may have a hyperbolic, spherical, cone, or combined shape. A charge coupled device (CCD) or a complementary metal oxide semiconductor (CMOS) is used as the image pickup device. An image (i.e., omni-directional image) projected on a pickup surface of the image pickup device is formed by reflection from the rotating reflector and shows a distorted image which is not proper for observation. Therefore, for accurate observation of an image, output coordinates of the image pickup device are converted through, for example, an external microprocessor to generate a new panoramic image.
An omni-directional image obtained through the omni-directional camera provides 2-dimensional information for the periphery of the camera (i.e., objects surrounding the camera, objects disposed around the camera, or images captured by the camera). If a plurality of omni-directional images photographed from different directions through a plurality of omni-directional cameras is used, 3-dimensional information for the periphery of the omni-directional cameras (i.e., objects surrounding the camera, objects disposed around the camera, or images captured by the camera) can be obtained. An image apparatus having a plurality of omni-directional cameras is called a stereo omni-directional camera. An omni-directional image photographed from the stereo omni-directional camera is used for location recognition of an unmanned vehicle or a mobile robot and for map generation, by equipping the unmanned vehicle or mobile robot with the stereo omni-directional camera.